Organometallic compound and organic light-emitting device including the same

ABSTRACT

Provided are an organometallic compound and an organic light-emitting device including the same. An organic layer of the organic light-emitting device includes an organometallic compound represented by Formula 1:

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2018-0163306, filed on Dec. 17, 2018,in the

Korean Intellectual Property Office, and entitled: “OrganometallicCompound and Organic Light-Emitting Device Including the Same,” isincorporated by reference herein in its entirety.

BACKGROUND 1. Field

Embodiments relate to an organometallic compound and an organiclight-emitting device including the same.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices that producefull-color images, and also have wide viewing angles, high contrastratios, short response times, and excellent characteristics in terms ofbrightness, driving voltage, and response speed, compared to devices inthe art.

An example of such organic light-emitting devices may include a firstelectrode disposed on a substrate, and a hole transport region, anemission layer, an electron transport region, and a second electrode,which are sequentially disposed on the first electrode. Holes providedfrom the first electrode may move toward the emission layer through thehole transport region, and electrons provided from the second electrodemay move toward the emission layer through the electron transportregion. Carriers, such as holes and electrons, recombine in the emissionlayer to produce excitons. These excitons transit from an excited stateto a ground state, thereby generating light.

SUMMARY

Embodiments are directed to an organic light-emitting device, includinga first electrode, a second electrode, and an organic layer between thefirst electrode and the second electrode and including an emissionlayer, the organic layer including an organometallic compoundrepresented by Formula 1:

wherein, in Formula 1,

M₁₁ may be platinum (Pt), palladium (Pd), copper (Cu), silver (Ag), gold(Au), rhodium (Rh), iridium (Ir), ruthenium (Ru), osmium (Os), titanium(Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), orthulium (Tm),

Y₁₀, Y₂₀, Y₃₀, and Y₄₀ may each independently be N or C,

Y₁₁, Y₁₂, Y₂₁, Y₂₂, Y₃₁, Y₃₂, Y₄₁, and Y₄₂ may each independently be Nor C,

A₁₀, A₂₀, A₃₀, and A₄₀ may each independently be a C₅-C₆ocarbocyclicgroup or a C₁-C₆₀ heterocyclic group,

T₁₁ to T₁₄ may each independently be a single bond, *—O—*′, or *—S—*′,

L₁₁ may be a substituted or unsubstituted C₃-C₁₀ cycloalkylene group,*—O—*′, *—S—*′, *—C(R₁)(R₂)—*′, *—C(R₁)═*′, *═C(R₁)—*′,*—C(R₁)═C(R₂)—*′, *—C(═S)—*′, *—B(R₁)—*′, *—N(R₁)—*′, *—P(R₁)—*′,*—Si(R₁)(R₂)—*′, *—P(R₁)(R₂)—*′, or *—Ge(R₁)(R₂)—*′,

a11 may be 1, 2, 3, 4, or 5,

at least one of L₁₁(s) in the number of a11 may be a substituted orunsubstituted C₃-C₁₀ cycloalkylene group,

L₁₂ to L₁₄ may each independently be a single bond, *—O—*′, *—S—*′,*—C(R₁)(R₂)—*′, *—C(R₁)═*′, *═C(R₁)—*′, *—C(R₁)═C(R₂)—*′, *—C(═O)—*′,*—C(═S)—*′, *—C≡C—*′, *—B(R₁)—*′, *—N(R₁)—*′, *—P(R₁)—*′,*—Si(R₁)(R₂)—*′, *—P(R₁)(R₂)—*′, or *-Ge(R₁)(R₂)—*′,

a12, a13, and a14 may each independently be 0, 1, 2, 3, 4, or 5,

R₁, R₂, R₁₀, R₂₀, R₃₀, and R₄₀ may each independently be hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedC₁-C₆₀ heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), or —P(═S)(Q₁)(Q₂),

R₁ and R₂ may be linked to form a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀ heterocyclicgroup,

R₁ and R₁₀; R₁ and R₂₀; R₁ and R₃₀; or R₁ and R₄₀ may be linked to forma substituted or unsubstituted C₅-C₆₀ carbocyclic group or a substitutedor unsubstituted C₁-C₆₀ heterocyclic group,

b10, b20, b30, and b40 may each independently be 1, 2, 3, 4, 5, 6, 7, or8,

* and *′ each indicate a binding site to a neighboring atom,

at least one substituent of the substituted C₅-C₆₀ carbocyclic group,the substituted C₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₆₀ alkyl group, the substitutedC₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, thesubstituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, ora C₁-C₆₀ alkoxy group, each substituted with deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂),—B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), or —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,or a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,or a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂),—B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), or —P(═O)(Q₂₁)(Q₂₂); or

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), or —P(═O)(Q₃₁)(Q₃₂), and

Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independentlybe hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a C₁-C₆₀ heteroaryloxygroup, a C₁-C₆₀ heteroarylthio group, a monovalent non-aromaticcondensed polycyclic group, a monovalent non-aromatic condensedheteropolycyclic group, a C₁-C₆₀ alkyl group substituted with deuterium,—F, or a cyano group, a C₆-C₆₀ aryl group substituted with deuterium,—F, or a cyano group, a biphenyl group, or a terphenyl group.

Embodiments are also directed to an organometallic compound representedby Formula 1.

BRIEF DESCRIPTION OF THE DRAWING

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with FIGURE which is a schematic view of an organiclight-emitting device according to an example embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter withreference to the accompanying drawing; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey exemplary implementations to those skilled in the art.

In the drawing figure, the dimensions of layers and regions may beexaggerated for clarity of illustration. Like reference numerals referto like elements throughout.

As used herein, the term “and/or” includes any and all combinations ofone or more of the associated listed items. Expressions such as “atleast one of,” when preceding a list of elements, modify the entire listof elements and do not modify the individual elements of the list.

An organometallic compound according to an example embodiment isrepresented by Formula 1:

In Formula 1, M₁₁ may be platinum (Pt), palladium (Pd), copper (Cu),silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium (Ru),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), or thulium (Tm).

In an example embodiment, M₁₁ may be Pt, Pd, Cu, Ag, or Au.

For example, M₁₁ may be Pt.

In Formula 1, Y₁₀, Y₂₀, Y₃₀, and Y₄₀ may each independently be N or C.

In an example embodiment, in Formula 1,

Y₁₀, Y₂₀, and Y₃₀ may each be C, and Y₄₀ may be N,

Y₁₀, Y₂₀, and Y₄₀ may each be C, and Y₃₀ may be N,

Y₁₀, Y₃₀, and Y₄₀ may each be C, and Y₂₀ may be N,

Y₂₀, Y₃₀, and Y₄₀ may each be C, and Y₁₀ may be N,

Y₁₀ and Y₄₀ may each be C, and Y₂₀ and Y₃₀ may each be N,

Y₁₀ and Y₄₀ may each be N, and Y₂₀ and Y₃₀ may each be C,

Y₁₀ and Y₂₀ may each be C, and Y₃₀ and Y₄₀ may each be N,

Y₁₀ and Y₂₀ may each be N, and Y₃₀ and Y₄₀ may each be C,

Y₁₀ and Y₃₀ may each be C, and Y₂₀ and Y₄₀ may each be N, or

Y₁₀ and Y₃₀ may each be N, and Y₂₀ and Y₄₀ may each be C.

In an example embodiment, at least one of Y₁₀ and Y₂₀ may be C,

(i) when Y₁₀ is C, a bond between Y₁₀ and T₁₁ or a bond between Y₁₀ andM₁₁ may be a coordinate bond, and

(ii) when Y₂₀ is C, a bond between Y₂₀ and T₁₂ or a bond between Y₂₀ andM₁₁ may be a coordinate bond.

In an example embodiment, Y₃₀ and Y₄₀ may each be C.

In Formula 1, A₁₀, A₂₀, A₃₀, and A₄₀ may each independently be a C₅-C₆₀carbocyclic group or a C₁-C₆₀ heterocyclic group.

In an example embodiment, A₁₀ to A₄₀ may each independently be a benzenegroup, a naphthalene group, an anthracene group, a phenanthrene group, atriphenylene group, a pyrene group, a chrysene group, a cyclopentadienegroup, a 1,2,3,4-tetrahydronaphthalene group, a furan group, a thiophenegroup, a silole group, an indene group, a fluorene group, an indolegroup, a carbazole group, a benzofuran group, a dibenzofuran group, abenzothiophene group, a dibenzothiophene group, a benzosilole group, adibenzosilole group, an indeno pyridine group, an indolopyridine group,a benzofuropyridine group, a benzothienopyridine group, abenzosilolopyridine group, an indeno pyrimidine group, anindolopyrimidine group, a benzofuropyrimidine group, abenzothienopyrimidine group, a benzosilolopyrimidine group, adihydropyridine group, a pyridine group, a pyrimidine group, a pyrazinegroup, a pyridazine group, a triazine group, a quinoline group, anisoquinoline group, a quinoxaline group, a quinazoline group, aphenanthroline group, a pyrrole group, a pyrazole group, an imidazolegroup, a 2,3-dihydroimidazole group, a triazole group, a2,3-dihydrotriazole group, an oxazole group, an isooxazole group, athiazole group, an isothiazole group, an oxadiazole group, a thiadiazolegroup, a benzopyrazole group, a benzimidazole group, a2,3-dihydrobenzimidazole group, an imidazopyridine group, a2,3-dihydroimidazopyridine group, an imidazopyrimidine group, a2,3-dihydroimidazopyrimidine group, an imidazopyrazine group, a2,3-dihydroimidazopyrazine group, a benzoxazole group, a benzothiazolegroup, a benzoxadiazole group, a benzothiadiazole group, a5,6,7,8-tetrahydroisoquinoline group, or a 5,6,7,8-tetrahydroquinolinegroup.

In an example embodiment, at least one of A₁₀ and A₂₀ may be anN-containing C₁-C₆₀ heterocyclic group.

In an example embodiment, A₁₀ and A₂₀ may each independently be anN-containing

C₁-C₆₀ heterocyclic group.

In an example embodiment, A₁₀ and A₂₀ may each independently be apyrrole group, a pyrazole group, an imidazole group, a2,3-dihydroimidazole group, a triazole group, a 2,3-dihydrotriazolegroup, an oxazole group, an isooxazole group, a thiazole group, anisothiazole group, an oxadiazole group, a thiadiazole group, abenzopyrazole group, a benzimidazole group, a 2,3-dihydrobenzimidazolegroup, an imidazopyridine group, a 2,3-dihydroimidazopyridine group, animidazopyrimidine group, a 2,3-dihydroimidazopyrimidine group, animidazopyrazine group, a 2,3-dihydroimidazopyrazine group, a benzoxazolegroup, a benzothiazole group, a benzoxadiazole group, a benzothiadiazolegroup, a pyridine group, a pyrimidine group, a pyrazine group, apyridazine group, a triazine group, a quinoline group, an isoquinolinegroup, a quinoxaline group, a quinazoline group, a phenanthroline groupa 5,6,7,8-tetrahydroisoquinoline group, or a 5,6,7,8-tetrahydroquinolinegroup.

In an example embodiment, at least one of A₁₀ and A₂₀ may be anN-containing 5-membered heterocyclic group or an N-containing 7-memberedheterocyclic group, or

at least one of A₁₀ and A₂₀ may be condensed with a 6-memberedcarbocyclic group or a 6-membered heterocyclic group.

In an example embodiment, A₁₀ and A₂₀ may each independently be anN-containing 5-membered heterocyclic group or an N-containing 7-memberedheterocyclic group, and

A₁₀ and A₂₀ may be condensed with a 6-membered carbocyclic group or a6-membered heterocyclic group.

In an example embodiment, A₁₀ and A₂₀ may each independently be a grouprepresented by one of Formulae 10-1 to 10-3:

In Formulae 10-1 to 10-3,

Y₁₃ to Y₁₈ and X₁₁ to X₁₄ may each independently be N or C(R₁₀),

R₁₀ is the same as described above, and

*, *′, and *″ each indicate a binding site to a neighboring atom.

In an example embodiment, A₃₀ and A₄₀ may each independently be a grouprepresented by one of Formulae 2-1 to 2-43:

In Formulae 2-1 to 2-43,

X₂₁ to X₂₃ may each independently be C(R₂₄) or C—* and at least two ofX₂₁ to X₂₃ may be C—*,

X₂₄ may be N—*.

X₂₅ and X₂₆ may each independently be C(R₂₄) or C—*, and at least one ofX₂₅ and X₂₆ may be C—*,

X₂₇ and X₂₈ may each independently be N, N(R₂₅), or N—*, and X₂₉ may beC(R₂₄) or C—*, wherein i) at least one of X₂₇ and X₂₈ may be N—*, andX₂₉ may be C—*, or ii) X₂₇ and X₂₈ may each be N—*, and X₂₉ may beC(R₂₄),

R₂₁ to R₂₅ may each independently be the same as described in connectionwith R₁₀,

b21 may be 1, 2, or 3,

b22 may be 1, 2, 3, 4, or 5,

b23 may be 1, 2, 3, or 4,

b24 may be 1 or 2, and

* indicates a binding site to a neighboring atom.

In an example embodiment, in Formula 1, A₃₀ and A₄₀ may eachindependently be a group represented by one of Formulae 2-1 to 2-9.

In an example embodiment, in Formula 1, A₃₀ and A₄₀ may eachindependently be a benzene group, a pyridine group, a pyrimidine group,or a triazine group.

In Formula 1, T₁₁ to T₁₄ may each independently be a single bond,*—O—*′, or *—S—*′.

In an example embodiment, in Formula 1, each of T₁₁ to T₁₄ may be asingle bond;

T₁₁ may be O or S, and T₁₂ to T₁₄ may each be a single bond;

T₁₂ may be O or S, and T₁₁, T₁₃, and T₁₄ may each be a single bond;

T₁₃ may be O or S, and T₁₁, T₁₂, and T₁₄ may each be a single bond; or

T₁₄ may be O or S, and T₁₁, T₁₂, and T₁₃ may each be a single bond.

For example, in Formula 1, each of T₁₁ to T₁₄ may each be a single bond.

In an example embodiment, a bond between Y₁₀ and T₁₁ or a bond betweenY₁₀ and M₁₁ may be a coordinate bond.

In an example embodiment, a bond between Y₂₀ and T₁₂ or a bond betweenY₂₀ and M₁₁ may be a coordinate bond.

In an example embodiment, a bond between Y₃₀ and T₁₃ or a bond betweenY₃₀ and M₁₁ may be a covalent bond.

In an example embodiment, a bond between Y₄₀ and T₁₄ or a bond betweenY₄₀ and M₁₁ may be a covalent bond.

In Formula 1, L₁₁ may be a substituted or unsubstituted C₃-C₁₀cycloalkylene group, *—O—*′, *—S—*′, *—C(R₁)(R₂)—*′, *—C(R₁)═*′,*═C(R₁)—*′, *—C(R₁)═C(R₂)—*′, *—C(═O)—*′, *—C(═S)—*′, *—B(R₁)—*′,*—N(R₁)—*′, *13 P(R₁)—*′, *—Si(R₁)(R₂)—*′, *—P(R₁)(R₂)—*′, or*—Ge(R₁)(R₂)—*′, a11 may be 1, 2, 3, 4, or 5, and at least one of L₁₁(s)in the number of a11 may be a substituted or unsubstituted C₃-C₁₀cycloalkylene group.

In an example embodiment, at least one of L₁₁(s) in the number of a11may be:

a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, acyclohexylene group, a cycloheptylene group, a cyclooctylene group, acyclononylene group, or a cyclodecanylene group; or

a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, acyclohexylene group, a cycloheptylene group, a cyclooctylene group, acyclononylene group, or a cyclodecanylene group, each substituted withdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, aphenanthrenyl group, an anthracenyl group, a triperylenyl group, apyridinyl group, a pyrimidinyl group, a carbazolyl group, a triazinylgroup, a dibenzofuranyl group, or a dibenzothiophenyl group.

In an example embodiment, at least one of L₁₁(s) in the number of a11may be a group represented by one of Formulae 3-1 to 3-5:

In Formulae 3-1 to 3-5,

R₃ may be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀alkynyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a phenanthrenyl group, an anthracenyl group, atriperylenyl group, a pyridinyl group, a pyrimidinyl group, a carbazolylgroup, a triazinyl group, a dibenzofuranyl group, or a dibenzothiophenylgroup,

b4 may be an integer from 1 to 4,

b6 may be an integer from 1 to 6,

b8 may be an integer from 1 to 8,

b10 may be an integer from 1 to 10,

b12 may be an integer from 1 to 12, and

* and *′ each indicate a binding site to a neighboring atom.

In an example embodiment, a11 may be 1, and

L₁₁ may be:

a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, acyclohexylene group, a cycloheptylene group, a cyclooctylene group, acyclononylene group, or a cyclodecanylene group; or

a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, acyclohexylene group, a cycloheptylene group, a cyclooctylene group, acyclononylene group, or a cyclodecanylene group, each substituted withdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkenyl group, a C₁-C₂₀ alkynyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, aphenanthrenyl group, an anthracenyl group, a triperylenyl group, apyridinyl group, a pyrimidinyl group, a carbazolyl group, a triazinylgroup, a dibenzofuranyl group, or a dibenzothiophenyl group.

In an example embodiment, a11 may be 1, and L₁₁ may be a grouprepresented by one of Formulae 3-1 to 3-5.

In Formula 1, L₁₂ to L₁₄ may each independently be a single bond,*—O—*′, *—S—*′, *—C(R₁)(R₂)—*′, *—C(R₁)═*′, *—C(R₁)═C(R₂)—*′,*—C(═O)—*′, *—C(═S)—*′, *—C≡C—*′, *—B(R₁)—*′, *—N(R₁)—*′, *—P(R₁)—*′,*—Si(R₁)(R₂)—*′, *—P(R₁)(R₂)—*′, or *—Ge(R₁)(R₂)—*′.

In an example embodiment, L₁₂ to L₁₄ may each independently be a singlebond, *—O—*′, *—S—*′, *—N(R₁)—*′, *—C(R₁)(R₂)—*′, *—Si(R₁)(R₂)—*′, or*—B(R₁)—*′.

In an example embodiment, in Formula 1, L₁₂ may be *—C(R₁)(R₂)—*′or*—Si(R₁)(R₂)—*′, and R₁ and R₂ may be linked to form a substituted orunsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstitutedC₁-C₆₀ heterocyclic group,

L₁₂ may be *—C(R₁)(R₂)—*′ for *—Si(R₁)(R₂)—*′, and R₁ and R₂ may belinked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic groupor a substituted or unsubstituted C₁-C₆₀ heterocyclic group, or

L₁₄ may be *—N(R₁)—*′, *—C(R₁)(R₂)—*′, or *—Si(R₁)(R₂)—*′, and R₁ and R₂may be linked to faint a substituted or unsubstituted C₅-C₆₀ carbocyclicgroup or a substituted or unsubstituted C₁-C₆₀ heterocyclic group.

In an example embodiment, in Formula 1, L₁₂ may be *—N(R₁)—*′,*—C(R₁)(R₂)—*′, or *—Si(R₁)(R₂)—*′, and R₁ and R₂₀ may be linked to forma substituted or unsubstituted C₅-C₆₀ carbocyclic group or a substitutedor unsubstituted C₁-C₆₀ heterocyclic group,

L₁₂ may be *—N(R₁)—*′, *—C(R₁)(R₂)—*′, or *—Si(R₁)(R₂)—*′, and R₁ andR₂₀; or R₁ and R₃₀ may be linked to form a substituted or unsubstitutedC₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₁-C₆₀heterocyclic group, or

L₁₄ may be *—N(R₁)—*′, *—(R₁)(R₂)—*′, or *—Si(R₁)(R₂)—*′, and R₁ and R₄₀may be linked to form a substituted or unsubstituted C₅-C₆₀ carbocyclicgroup or a substituted or unsubstituted C₁-C₆₀ heterocyclic group.

In an example embodiment, in Formula 1, L₁₂ and L₁₄ may each be a singlebond, and

L₁₃ may be *—O—*′, *—S—*′, *—N(R₁)—*′, *—C(R₁)(R₂)—*′, *—Si(R₁)(R₂)—*′,or *—B(R₁)—*′.

In Formula 1, a12, a13, and a14 may each independently be 0, 1, 2, 3, 4,or 5. When a12 is 0, A₂₀ and A₃₀ may not be linked, when a13 is 0, A₃₀and A₄₀ may not be linked, and when a14 is 0, A₃₀ and A₄₀ may not belinked.

In an example embodiment, a12, a13, and a14 may each independently be 1,2, or 3

In Formula 1, Ri, R₂, Rio, R₂₀, R₃₀, and R₄o may each independently behydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedC₁-C₆₀ heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), or —P(═S)(Q₁)(Q₂),

R₁ and R₁₀; R₁ and R₂₀; R₁ and R₃₀; or R₁ and R₄₀ may be linked to forma substituted or unsubstituted C₅-C₆₀ carbocyclic group or a substitutedor unsubstituted C₁-C₆₀ heterocyclic group,

b10, b20, b30, and b40 may each independently be 1, 2, 3, 4, 5, 6, 7, or8, and

Q₁ to Q₃ may each independently be hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, aC₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, or a terphenylgroup.

In an example embodiment, R₁, R₂, R₁₀, R₂₀, R₃₀, and R₄₀ may eachindependently be:

hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀ alkylgroup, or a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group or a C₁-C₂₀ alkoxy group, each substituted withdeuterium, —F, —Cl, —Br, —I, a cyano group, a phenyl group, or abiphenyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a pentalenyl group, an indenyl group, anaphthyl group, an azulenyl group, an indacenyl group, an acenaphthenylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a perylenyl group, apentacenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group,a silolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an indolyl group, an isoindolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a benzoisoquinolinyl group, a phthalazinyl group,a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group,a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, a benzosilolyl group, a benzothiazolyl group, abenzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group,a triazolyl group, a tetrazolyl group, a thiadiazolyl group, anoxadiazolyl group, a triazinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group,a benzocarbazolyl group, a naphthobenzofuranyl group, anaphthobenzothiophenyl group, a naphthobenzosilolyl group, adibenzocarbazolyl group, a dinaphthofuranyl group, a dinaphthothiophenylgroup, a dinaphtho silolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an oxazolopyridinyl group, a thiazolopyridinylgroup, a benzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group, anindenopyrrolyl group, an indolopyrrolyl group, an indeno carbazolylgroup, or an indolocarbazolyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a pentalenyl group, an indenyl group, anaphthyl group, an azulenyl group, an indacenyl group, an acenaphthenylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a perylenyl group, apentacenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group,a silolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an indolyl group, an isoindolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a benzoisoquinolinyl group, a phthalazinyl group,a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group,a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, a benzosilolyl group, a benzothiazolyl group, abenzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group,a triazolyl group, a tetrazolyl group, a thiadiazolyl group, anoxadiazolyl group, a triazinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group,a benzocarbazolyl group, a naphthobenzofuranyl group, anaphthobenzothiophenyl group, a naphthobenzosilolyl group, adibenzocarbazolyl group, a dinaphthofuranyl group, a dinaphthothiophenylgroup, a dinaphtho silolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an oxazolopyridinyl group, a thiazolopyridinylgroup, a benzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group, anindenopyrrolyl group, an indolopyrrolyl group, an indeno carbazolylgroup, or an indolocarbazolyl group, each substituted with deuterium,—F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a pentalenyl group, an indenyl group, anaphthyl group, an azulenyl group, an indacenyl group, an acenaphthenylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a perylenyl group, apentacenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group,a silolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an indolyl group, an isoindolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a benzoisoquinolinyl group, a phthalazinyl group,a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group,a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, a benzosilolyl group, a benzothiazolyl group, abenzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group,a triazolyl group, a tetrazolyl group, a thiadiazolyl group, anoxadiazolyl group, a triazinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group,a benzocarbazolyl group, a naphthobenzofuranyl group, anaphthobenzothiophenyl group, a naphthobenzosilolyl group, adibenzocarbazolyl group, a dinaphthofuranyl group, a dinaphthothiophenylgroup, a dinaphtho silolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an oxazolopyridinyl group, a thiazolopyridinylgroup, a benzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group, anindenopyrrolyl group, an indolopyrrolyl group, an indeno carbazolylgroup, an indolocarbazolyl group, —Si(Q₃₀(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)(Q₃₁), —S(═O)₂(Q₃₁), —P(═O)(Q₃₁)(Q₃₂),or —P(═S)(Q₃₁)(Q₃₂); or

—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═))(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), or —P(═S)(Q₁)(Q₂), and

Q₁ to Q₃ and Q₃₁ to Q₃₃ may each independently be hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a C₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthiogroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a C₁-C₆₀ alkylgroup substituted with at least deuterium, —F, or a cyano group, aC₆-C₆₀ aryl group substituted with deuterium, —F, or a cyano group, abiphenyl group, or a terphenyl group.

In an example embodiment, R₁, R₂, R₁₀, R₂₀, R₃₀, and R₄₀ may eachindependently be:

hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀ alkylgroup, or a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group or a C₁-C₂₀ alkoxy group, each substituted withdeuterium, —F, —Cl, —Br, —I, a cyano group, a phenyl group, or abiphenyl group;

a group represented by one of Formulae 5-1 to 5-25; or

a group represented by one of Formulae 6-1 to 6-55, and

R₁ and R₂ may be linked to form a cyclopentane group, a cyclohexanegroup, a benzene group, a naphthalene group, or a fluorene group,

In Formulae 5-1 to 5-25 and 6-1 to 6-55,

Y₃₁ may be O, S, C(Z₃₄)(Z₃₅), N(Z₃₄), Or Si(Z₃₄)(Z₃₅),

Z₃₁ to Z₃₅ may each independently be hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₂-C₂₀alkenyl group, a C₂-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a phenanthrenyl group, ananthracenyl group, a triperylenyl group, a pyridinyl group, apyrimidinyl group, a carbazolyl group, or a triazinyl group,

e2 may be 1 or 2,

e3 may be an integer from 1 to 3,

e4 may be an integer from 1 to 4,

e5 may be an integer from 1 to 5,

e6 may be an integer from 1 to 6,

e7 may be an integer from 1 to 7,

e9 may be an integer from 1 to 9, and

* indicates a binding site to a neighboring atom.

In an example embodiment, R₁, R₂, R₁₀, R₂₀, R₃₀, and R₄₀ may eachindependently be:

hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀ alkylgroup, or a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group or a C₁-C₂₀ alkoxy group, each substituted withdeuterium, —F, —Cl, —Br, —I, a cyano group, a phenyl group, or abiphenyl group;

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, an indacenylgroup, an acenaphthenyl group, a fluorenyl group, a spiro-bifluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a carbazolylgroup, an acridinyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, or a dibenzocarbazolyl group; or

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, an indacenylgroup, an acenaphthenylgroup, a fluorenyl group, a spiro-bifluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a carbazolylgroup, an acridinyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, or a dibenzocarbazolyl group, eachsubstituted with deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, or a biphenyl group,and

R₁ and R₂ may be linked to form a cyclopentane group, a cyclohexanegroup, or a fluorene group.

In an example embodiment, the organometallic compound may be one ofCompounds 1 to 40:

In an example embodiment, the organometallic compound represented byFormula 1 has a structure in which at least one of L₁₁(s) in the numberof a11 is a substituted or unsubstituted C₃-C₁₀ cycloalkylene group.Without being bound by theory, it is believed that, since thecycloalkylene group is positioned outside a plane (in which a metal M₁₁and rings A₁₁ to A₁₄ are included) to form a three-dimensionalstructure, interaction with other molecules may be suppressed, and theformation of excimer and exciplex may be inhibited. Therefore, when theorganometallic compound represented by Formula 1 according to thepresent example embodiment is applied to the organic light-emittingdevice, it may be advantageous to energy transfer, luminance efficiencymay be high, high color purity may be realized, and lifespancharacteristics may be improved.

In addition, when ring A₁₀ in the organometallic compound represented byFormula 1 is carbene, high color purity and excellent lifespancharacteristics may be provided due to strong σ-donation andπ-backdonation effects.

In an example embodiment, the organometallic compound represented byFormula 1 includes a moiety providing a rigid structure. Thus, anorganic light-emitting device including the organometallic compound mayhave high durability and a long lifespan.

The organometallic compound may emit blue light. For example, theorganometallic compound may emit blue light (bottom emission CIE_(x,y)color coordinates 0.135, 0.15 to 0.30) having a wavelength of maximumemission of about 440 nm to about 500 nm, for example, a wavelength ofmaximum emission of about 460 nm to about 495 nm. Therefore, theorganometallic compound represented by Formula 1 may be usefully used tomanufacture an organic light-emitting device that emits blue light.

A synthesis method for the organometallic compound represented byFormula 1 will be apparent to those of skill in the art by referring tothe examples below.

At least one of the organometallic compound of Formula 1 may be usedbetween a pair of electrodes of an organic light-emitting device. Forexample, the organometallic compound may be included in an emissionlayer. The organometallic compound may act as a dopant in the emissionlayer.

According to an example embodiment, an organic light-emitting deviceincludes a first electrode, a second electrode facing the firstelectrode, and an organic layer between the first electrode and thesecond electrode. The organic layer may include an emission layer. Theorganic layer may include at least one organometallic compoundrepresented by Formula 1.

The expression “(an organic layer) includes at least one organometalliccompound” as used herein may include a case in which “(an organic layer)includes identical compounds represented by Formula 1” and a case inwhich “(an organic layer) includes two or more different organometalliccompounds represented by Formula 1.”

For example, the organic layer may include, as the organometalliccompound, only Compound 1. In this regard, Compound 1 may exist in anemission layer of the organic light-emitting device. In an exampleembodiment, the organic layer may include, as the organometalliccompound, Compound 1 and Compound 2. In this regard, Compound 1 andCompound 2 may exist in an identical layer (for example, Compound 1 andCompound 2 may all exist in an emission layer), or different layers (forexample, Compound 1 may exist in an emission layer and Compound 2 mayexist in an electron transport region).

In an example embodiment,

the first electrode of the organic light-emitting device may be ananode,

the second electrode of the organic light-emitting device may be acathode,

the organic layer may further include a hole transport region betweenthe first electrode and the emission layer and an electron transportregion between the emission layer and the second electrode,

the hole transport region may include a hole injection layer, a holetransport layer, an emission auxiliary layer, an electron blockinglayer, or a combination thereof, and

the electron transport region may include a hole blocking layer, anelectron transport layer, an electron injection layer, or a combinationthereof.

The term “organic layer” as used herein refers to a single layer and/ora plurality of layers disposed between the first electrode and thesecond electrode of the organic light-emitting device. A materialincluded in the “organic layer” is not limited to an organic material.

In an example embodiment, the emission layer may include anorganometallic compound represented by Formula 1, and may furtherinclude a host, wherein an amount of the host in the emission layer maybe greater than that of the organometallic compound in the emissionlayer.

In an example embodiment, the emission layer may further include a host,and the host may include a silyl-containing compound, a phosphineoxide-containing compound, or a combination thereof.

In an example embodiment, the hole transport region may include anelectron blocking layer, and the electron blocking layer may include theorganometallic compound; or

the electron transport region may include a hole blocking layer, and thehole blocking layer may include the organometallic compound.

In an example embodiment, the hole transport region may include ap-dopant having a lowest unoccupied molecular orbital (LUMO) energylevel of about −3.5 eV or less.

In an example embodiment, the electron transport region may include ahole blocking layer, and the hole blocking layer may directly contactthe emission layer, and the hole blocking layer may include a phosphineoxide-containing compound or a silyl-containing compound.

DESCRIPTION OF THE FIGURE

The FIGURE is a schematic view of an organic light-emitting device 10according to an example embodiment. The organic light-emitting device 10includes a first electrode 110, an organic layer 150, and a secondelectrode 190.

Hereinafter, the structure of the organic light-emitting device 10according to an example embodiment and a method of manufacturing theorganic light-emitting device 10 will be described in connection withthe FIGURE.

[First Electrode 110]

In the FIGURE, a substrate may be additionally disposed under the firstelectrode 110 or above the second electrode 190. The substrate may be aglass substrate or a plastic substrate, each having excellent mechanicalstrength, thermal stability, transparency, surface smoothness, ease ofhandling, and water resistance.

The first electrode 110 may be formed by depositing or sputtering amaterial for forming the first electrode 110 on the substrate. When thefirst electrode 110 is an anode, the material for a first electrode maybe selected from materials with a high work function to facilitate holeinjection.

The first electrode 110 may be a reflective electrode, asemi-transmissive electrode, or a transmissive electrode. When the firstelectrode 110 is a transmissive electrode, a material for forming afirst electrode may be selected from indium tin oxide (ITO), indium zincoxide (ILO), tin oxide (SnO₂), zinc oxide (ZnO), and a combinationsthereof. In an example embodiment, when the first electrode 110 is asemi-transmissive electrode or a reflective electrode, a material forforming a first electrode may be selected from magnesium (Mg), silver(Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca),magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), and a combinationsthereof.

The first electrode 110 may have a single-layered structure, or amulti-layered structure including two or more layers. For example, thefirst electrode 110 may have a three-layered structure of ITO/Ag/ITO.

[Organic Layer 150]

The organic layer 150 is disposed on the first electrode 110. Theorganic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport regionbetween the first electrode 110 and the emission layer, and an electrontransport region between the emission layer and the second electrode190.

[Hole Transport Region in Organic Layer 150]

The hole transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from ahole injection layer, a hole transport layer, an emission auxiliarylayer, and an electron blocking layer.

For example, the hole transport region may have a single-layeredstructure including a single layer including a plurality of differentmaterials, or a multi-layered structure having a hole injectionlayer/hole transport layer structure, a hole injection layer/holetransport layer/emission auxiliary layer structure, a hole injectionlayer/emission auxiliary layer structure, a hole transportlayer/emission auxiliary layer structure, or a hole injection layer/holetransport layer/electron blocking layer structure, wherein for eachstructure, constituting layers may be sequentially stacked from thefirst electrode 110 in this stated order.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB(NPD), β-NPB, TPD, Spiro-TPD, Spiro-NPB,methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine(TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (PANI/CSA),polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound representedby Formula 201, and a compound represented by Formula 202:

In Formulae 201 and 202,

L₂₀₁ to L₂₀₄ may each independently be selected from a substituted orunsubstituted

C₃-C₁₀ cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

L₂₀₅ may be selected from *—O—*′, *—S—*′, *—N(Q₂₀₁)—*′, a substituted orunsubstituted C₁-C₂₀ alkylene group, a substituted or unsubstitutedC₂-C₂₀ alkenylene group, a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xa1 to xa4 may each independently be an integer of 0 to 3,

xa5 may be an integer of 1 to 10, and

R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₆₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group.

For example, in Formula 202, R₂₀₁ and R₂₀₂ may be linked via a singlebond, a dimethyl-methylene group, or a diphenyl-methylene group, andR₂₀₃ and R₂₀₄ may be linked via a single bond, a dimethyl-methylenegroup, or a diphenyl-methylene group.

In an example embodiment, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from:

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthenylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthenylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthenyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In an example embodiment, xa1 to xa4 may each independently be 0, 1, or2.

In an example embodiment, xa5 may be 1, 2, 3, or 4.

In an example embodiment, R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independentlybe selected from:

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthenyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthenyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthenyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ are the same as described above.

In an example embodiment, in Formula 201, at least one selected fromR₂₀₁ to R₂₀₃ may each independently be selected from:

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkylgroup, a phenyl group substituted with —F, a naphthyl group, a fluorenylgroup, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranylgroup, and a dibenzothiophenyl group.

In an example embodiment, in Formula 202, i) R₂₀₁ and R₂₀₂ may be linkedvia a single bond, and/or ii) R₂₀₃ and R₂₀₄ may be linked via a singlebond.

In an example embodiment, in Formula 202, at least one selected fromR₂₀₁ to R₂₀₄ may each independently selected from:

a carbazolyl group; and

a carbazolyl group substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, acarbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group.

The compound represented by Formula 201 may be represented by Formula201A:

For example, the compound represented by Formula 201 may be representedby Formula 201A(1):

For example, the compound represented by Formula 201 may be representedby

Formula 201A-1:

For example, the compound represented by Formula 202 may be representedby Formula 202A:

For example, the compound represented by Formula 202 may be representedby Formula 202A-1:

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

L₂₀₁ to L₂₀₃, xa1 to xa3, xa5 and R₂₀₂, to R₂₀₄ are the same asdescribed above,

R₂₁₁ and R₂₁₂ may each independently be the same as defined inconnection with R₂₀₃, and

R₂₁₃ to R₂₁₇ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthenyl group, afluorenyl group, a Spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group.

The hole transport region may include at least one compound selectedfrom Compounds HT₁ to HT_(39:)

A thickness of the hole transport region may be in a range of about 100Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When thehole transport region includes at least one of a hole injection layerand a hole transport layer, a thickness of the hole injection layer maybe in a range of about 100 Å to about 9,000 Å, for example, about 100 Åto about 1,000 Å, and a thickness of the hole transport layer may be ina range of about 50 Å to about 2,000 Å, for example about 100 Å to about1,500 Å. When the thicknesses of the hole transport region, the holeinjection layer, and the hole transport layer are within these ranges,satisfactory hole transporting characteristics may be obtained without asubstantial increase in driving voltage.

The emission auxiliary layer may increase light-emission efficiency bycompensating for an optical resonance distance according to thewavelength of light emitted by an emission layer, and the electronblocking layer may block the flow of electrons from an electrontransport region. The emission auxiliary layer and the electron blockinglayer may include the materials as described above.

[p-dopant]

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or non-homogeneously dispersed in the hole transportregion.

The charge-generation material may be, for example, a p-dopant.

In an example embodiment, the p-dopant may have a LUMO energy level ofabout −3.5 eV or less.

The p-dopant may include at least one selected from a quinonederivative, a metal oxide, and a cyano group-containing compound.

For example, the p-dopant may include at least one selected from:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) or2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide or molybdenum oxide;

1,4,5,8,9,12-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

a compound represented by Formula 221:

In Formula 221,

R₂₂₁ to R₂₂₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, wherein at least oneselected from R₂₂₁ to R₂₂₃ may have at least one substituent selectedfrom a cyano group, —F, —Cl, —Br, —I, a C₁-C₂₀ alkyl group substitutedwith —F, a C₁-C₂₀ alkyl group substituted with —Cl, a C₁-C₂₀ alkyl groupsubstituted with —Br, and a C₁-C₂₀ alkyl group substituted with —I.

[Emission Layer in Organic Layer 150]

When the organic light-emitting device 10 is a full-color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, or a blue emission layer,according to a sub-pixel. In an example embodiment, the emission layermay have a stacked structure of two or more layers selected from a redemission layer, a green emission layer, and a blue emission layer, inwhich the two or more layers contact each other or are separated fromeach other. In an example embodiment, the emission layer may include twoor more materials selected from a red light-emitting material, a greenlight-emitting material, and a blue light-emitting material, in whichthe two or more materials are mixed with each other in a single layer toemit white light.

The emission layer may include a host and a dopant. The dopant mayinclude at least one selected from a phosphorescent dopant and afluorescent dopant. The phosphorescent dopant may include theorganometallic compound represented by Formula 1:

In the emission layer, an amount of the dopant may be in a range ofabout 0.01 parts by weight to about 15 parts by weight based on 100parts by weight of the host.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, for example, about 200 Å to about 600 Å. When thethickness of the emission layer is within this range, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

[Host in Emission Layer]

In an example embodiment, the host may include a compound represented byFormula 301:

[Ar₃₀₁]_(xb11)-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb21)   <Formula 301>

In Formula 301,

Ar₃₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xb11 may be 1, 2, or 3,

L₃₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xb1 may be an integer of 0 to 5,

R₃₀₁ may be selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), —N(Q₃₀₁)(Q₃₀₂),—B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), and —P(═O)(Q₃₀₁)(Q₃₀₂),

xb21 may be an integer of 1 to 5,

Q₃₀₁ to Q₃₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In an example embodiment, Ar₃₀₁ in Formula 301 may be selected from:

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup; and

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂),—C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In Formula 301, when xb11 is two or more, two or more Ar₃₀₁(s) may belinked via a single bond.

In an example embodiment, the compound represented by Formula 301 may berepresented by Formula 301-1 or 301-2:

In Formulae 301-1 to 301-2,

A₃₀₁ to A₃₀₄ may each independently be selected from a benzene group, anaphthalene group, a phenanthrene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a pyridine group,a pyrimidine group, an indene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,an indole group, a carbazole group, a benzocarbazole group, adibenzocarbazole group, a furan group, a benzofuran group, adibenzofuran group, a naphthofuran group, a benzonaphthofuran group, adinaphthofuran group, a thiophene group, a benzothiophene group, adibenzothiophene group, a naphthothiophene group, abenzonaphthothiophene group, and a dinaphthothiophene group,

X₃₀₁ may be O, S, or N-[(L₃₀₄)_(xb4)-R_(304],)

R₃₁₁ to R₃₁₄ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

xb22 and xb23 may each independently be 0, 1, or 2,

L₃₀₁, xb1, R₃₀₁, and Q₃₁ to Q₃₃ are the same as described above,

L₃₀₂ to L₃₀₄ may each independently be the same as defined in connectionwith L₃₀₁,

xb2 to xb4 may each independently be the same as defined in connectionwith xb1, and

R₃₀₂ to R₃₀₄ may each independently be the same as defined in connectionwith R₃₀₁.

For example, in Formulae 301, 301-1, and 301-2, L₃₁ to L₃₀₄ may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ are the same as described above.

In an example embodiment, in Formulae 301, 301-1, and 301-2, R₃₀₁ toR₃₀₄ may each independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ are the same as described above.

In an example embodiment, the host may include an alkaline earth metalcomplex. For example, the host may be selected from a Be complex (forexample, Compound H55), a Mg complex, and a Zn complex.

The host may include at least one selected from9,10-di(2-naphthyl)anthracene (ADN),2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN),9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN),4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene(mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55:

In an example embodiment, the host may include at least one selectedfrom a silicon-containing compound (for example, BCPDS in the followingexamples) and a phosphine oxide-containing compound (for example, POPCPAin the following examples).

In an example embodiment, the host may include only one compound, or twoor more different compounds (for example, a host used in the followingexamples includes BCPDS and POPCPA).

[Phosphorescent Dopant Included in Emission Layer in Organic Layer 150]

The phosphorescent dopant may include an organometallic compoundrepresented by Formula 1:

The phosphorescent dopant may include an organometallic complexrepresented by Formula 401:

In Formulae 401 and 402,

M may be selected from iridium (Ir), platinum (Pt), palladium (Pd),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), rhodium (Rh), and thulium (Tm),

L₄₀₁ may be selected from ligands represented by Formula 402, and xc1may be 1, 2, or 3, wherein, when xc1 is two or more, two or more L₄₀₁(s)may be identical to or different from each other,

L₄₀₂ may be an organic ligand, and xc2 may be an integer of 0 to 4,wherein, when xc2 is two or more, two or more L₄₀₂(5) may be identicalto or different from each other,

X₄₀₁ to X₄₀₄ may each independently be nitrogen or carbon,

X₄₀₁ and X₄₀₃ may be linked via a single bond or a double bond, and X₄₀₂and X₄₀₄ may be linked via a single bond or a double bond,

A₄₀₁ and A₄₀₂ may each independently be selected from a C₅-C₆₀carbocyclic group or a C₁-C₆₀ heterocyclic group,

X₄₀₅ may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q₄₁₁)—*′,*—C(Q₄₁₁)(Q₄₁₂)—′*, *—C(Q₄₁₁)═C(Q₄₁₂)—*′, *—C(Q₄₁₁)═*′, or *═C═*′,wherein Q₄₁₁ and Q₄₁₂ may each independently be hydrogen, deuterium, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, or a naphthyl group,

X₄₀₆ may be a single bond, O, or S,

R₄₀₁ and R₄₀₂ may each independently be selected from hydrogen,deuterium, —F, —CI, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₂₀ alkyl group, a substituted orunsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₆-C₆₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂),—B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂),wherein Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a C₆-C₂₀ aryl group, and a C₁-C₂₀heteroaryl group,

xc11 and xc12 may each independently be an integer of 0 to 10, and

in Formula 402, * and *′ each indicate a binding site to M in Formula401.

In an example embodiment, in Formula 402, A₄₀₁ and A₄₀₂ may eachindependently be selected from a benzene group, a naphthalene group, afluorene group, a spiro-bifluorene group, an indene group, a pyrrolegroup, a thiophene group, a furan group, an imidazole group, a pyrazolegroup, a thiazole group, an isothiazole group, an oxazole group, anisoxazole group, a pyridine group, a pyrazine group, a pyrimidine group,a pyridazine group, a quinoline group, an isoquinoline group, abenzoquinoline group, a quinoxaline group, a quinazoline group, acarbazole group, a benzimidazole group, a benzofuran group, abenzothiophene group, an isobenzothiophene group, a benzoxazole group,an isobenzoxazole group, a triazole group, a tetrazole group, anoxadiazole group, a triazine group, a dibenzofuran group, and adibenzothiophene group.

In an example embodiment, in Formula 402, i) X₄₀₁ may be nitrogen, andX₄₀₂ may be carbon, or ii) X₄₀₁ and X₄₀₂ may each be nitrogen at thesame time.

In an example embodiment, R₄₀₁ and R₄₀₂ in Formula 402 may eachindependently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a phenyl group, a naphthyl group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, and a norbornenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

—Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁),—S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂), and

Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, and anaphthyl group.

In an example embodiment, when xcl in Formula 401 is two or more, twoA₄₀₁(s) in two or more L₄₀₁(s) may be linked via X₄₀₇, which is alinking group, or two A₄₀₂(s) in two or more L₄₀₁(s) may be linked viaX₄₀₈, which is a linking group (see Compounds PD1 to PD4 and PD7). X₄₀₇and X₄₀₈ may each independently be a single bond, *—O—*′, *—S—*′,*—C(═O)—*′, *—N(Q₄₁₃)—*′, *—C(Q₄₁₃)(Q₄₁₄)—*′, or *—C(Q₄₁₃)═C(Q₄₁₄)—*?(wherein Q₄₁₃ and Q₄₁₄ may each independently be hydrogen, deuterium, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, or a naphthyl group).

L₄₀₂ in Formula 401 may be a monovalent, divalent, or trivalent organicligand. For example, L₄₀₂ may be selected from halogen, diketone (forexample, acetylacetonate), carboxylic acid (for example, picolinate),—C(═O), isonitrile, -CN, and phosphorus (for example, phosphine, orphosphite).

In an example embodiment, the phosphorescent dopant may be selectedfrom, for example, Compounds PD1 to PD25:

[Fluorescent Dopant in Emission Layer]

The fluorescent dopant may further include an arylamine compound or astyrylamine compound.

The fluorescent dopant may include a compound represented by Formula501:

In Formula 501,

Ar₅₀₁ may be a substituted or unsubstituted C₅-C₆ocarbocyclic group or asubstituted or unsubstituted C₁-C₆₀ heterocyclic group,

L₅₀₁ to L₅₀₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xd1 to xd3 may each independently be an integer of 0 to 3;

R₅₀₁ and R₅₀₂ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ to heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆ ⁻C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,

xd4 may be an integer of 1 to 6.

In an example embodiment, Ar₅₀₁ in Formula 501 may be selected from:

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup; and

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In an example embodiment, L₅₀₁ to L₅₀₃ in Formula 501 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group.

In an example embodiment, R₅₀₁ and R₅₀₂ in Formula 501 may eachindependently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In an example embodiment, xd4 in Formula 501 may be 2.

For example, the fluorescent dopant may be selected from Compounds FD1to FD22:

In an example embodiment, the fluorescent dopant may be selected fromthe following compounds.

[Electron Transport Region in Organic Layer 150]

The electron transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron transport region may include at least one selected from abuffer layer, a hole blocking layer, an electron control layer, anelectron transport layer, and an electron injection layer.

For example, the electron transport region may have an electrontransport layer/electron injection layer structure, a hole blockinglayer/electron transport layer/electron injection layer structure, anelectron control layer/electron transport layer/electron injection layerstructure, or a buffer layer/electron transport layer/electron injectionlayer structure, wherein for each structure, constituting layers may besequentially stacked from an emission layer.

The electron transport region (for example, a buffer layer, a holeblocking layer, an electron control layer, or an electron transportlayer in the electron transport region) may include a metal-freecompound containing at least one π electron-depleted nitrogen-containingring.

The “π electron-depleted nitrogen-containing ring” indicates a C₁-C₆₀heterocyclic group having at least one *—N═*′ moiety as a ring-formingmoiety.

For example, the “π electron-depleted nitrogen-containing ring” may bei) a 5-membered to 7-membered heteromonocyclic group having at least one*—N═*′ moiety, ii) a heteropolycyclic group in which two or more5-membered to 7-membered heteromonocyclic groups each having at leastone *—N═*′ moiety are condensed with each other, or iii) aheteropolycyclic group in which at least one of 5-membered to 7-memberedheteromonocyclic groups, each having at least one *—N═*′ moiety, iscondensed with at least one C₅-C₆₀ carbocyclic group.

Examples of the π electron-depleted nitrogen-containing ring include animidazole group, a pyrazole group, a thiazole group, an isothiazolegroup, an oxazole group, an isoxazole group, a pyridine group, apyrazine group, a pyrimidine group, a pyridazine group, an indazolegroup, a purine group, a quinoline group, an isoquinoline group, abenzoquinoline group, a phthalazine group, a naphthyridine group, aquinoxaline group, a quinazoline group, a cinnoline group, aphenanthridine group, an acridine group, a phenanthroline group, aphenazine group, a benzimidazole group, an isobenzothiazole group, abenzoxazole group, an isobenzoxazole group, a triazole group, atetrazole group, an oxadiazole group, a triazine group, a thiadiazolgroup, an imidazopyridine group, an imidazopyrimidine group, and anazacarbazole group.

For example, the electron transport region may include a compoundrepresented by Formula 601:

[Ar₆₀₁]_(xe11)-[(L₆₀₁)_(xe1)-R₆₀₁₁]_(xe21)   <Formula 601>

In Formula 601,

Ar₆₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xe11 may be 1, 2, or 3,

L₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group;

xe1 may be an integer of 0 to 5,

R₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃), —C(═O)(Q₆₀₁),—S(═O)₂(Q₆₀₁), and —P(═O)(Q₆₀₁)(Q₆₀₂),

Q₆₀₁ to Q₆₀₃ may each independently be a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or anaphthyl group, and

xe21 may be an integer of 1 to 5.

In an example embodiment, at least one of Ar₆₀₁(s) in the number of xe11and R₆₀₁(s) in the number of xe21 may include the it electron-depletednitrogen-containing ring.

In an example embodiment, Ar₆₀₁ in Formula 601 may be selected from:

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an isobenzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group; and

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an isobenzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

When xe11 in Formula 601 is two or more, two or more Ar₆₀₁(s) may belinked via a single bond.

In an example embodiment, Ar₆₀₁ in Formula 601 may be an anthracenegroup.

In an example embodiment, a compound represented by Formula 601 may berepresented by Formula 601-1:

In Formula 601-1,

X₆₁₄ may be N or C(R614), X615 may be N or C(R₆₁₅), and X₆₁₆ may be N orC(R₆₁₆), wherein at least one selected from X614 to X616 may be N,

L₆₁₁ to L₆₁₃ may each independently be the same as defined in connectionwith L₆₀₁,

xe611 to xe613 may each independently be the same as defined inconnection with xe1,

R₆₁₁ to R613 may each independently be the same as defined in connectionwith R₆₀₁, and

R₆₁₄ to R₆₁₆ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In an example embodiment, L₆₀₁ and L₆₁₁ to L₆₁₃ in Formulae 601 and601-1 may each independently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group.

In an example embodiment, xe1 and xe611 to xe613 in Formulae 601 and601-1 may each independently be 0, 1, or 2.

In an example embodiment, in Formulae 601 and 601-1, R₆₀₁ and R611 toR₆₁₃ may each independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

—S(═O)₂(Q₆₀₁) and —P(═O)(Q₆₀₁)(Q₆₀₂), and

Q₆₀₁ and Q₆₀₂ may be the same as described above.

The electron transport region may include at least one compound selectedfrom Compounds ET1 to ET36:

In an example embodiment, the electron transport region may include atleast one compound selected from2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP),4,7-diphenyl-1,10-phenanthroline (Bphen), Alq₃, BAlq,3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ), and NTAZ:

In an example embodiment, the electron transport region may include aphosphine oxide-containing compound (for example, TSPO1 used in thefollowing examples). In an example embodiment, the phosphineoxide-containing compound may be used in a hole blocking layer in theelectron transport region.

A thickness of the buffer layer, the hole blocking layer, or theelectron control layer may be in a range of about 20 Å to about 1,000 Å,for example, about 30 Å to about 300 Å. When the thicknesses of thebuffer layer, the hole blocking layer, and the electron control layerare within these ranges, the electron transport region may haveexcellent hole blocking characteristics or electron controlcharacteristics without a substantial increase in driving voltage.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Whenthe thickness of the electron transport layer is within the rangedescribed above, the electron transport layer may have satisfactoryelectron transport characteristics without a substantial increase indriving voltage.

The electron transport region (for example, the electron transport layerin the electron transport region) may further include, in addition tothe materials described above, a metal-containing material.

The metal-containing material may include at least one selected fromalkali metal complex and alkaline earth-metal complex. The alkali metalcomplex may include a metal ion selected from a Li ion, a Na ion, a Kion, a Rb ion, and a Cs ion, and the alkaline earth-metal complex mayinclude a metal ion selected from a Be ion, a Mg ion, a Ca ion, a Srion, and a Ba ion. A ligand coordinated with the metal ion of the alkalimetal complex or the alkaline earth-metal complex may be selected from ahydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, ahydroxy acridine, a hydroxy phenanthridine, a hydroxy phenyloxazole, ahydroxy phenylthiazole, a hydroxy diphenyloxadiazole, a hydroxydiphenylthiadiazol, a hydroxy phenylpyridine, a hydroxyphenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, aphenanthroline, and a cyclopentadiene.

For example, the metal-containing material may include a Li complex. TheLi complex may include, for example, Compound ET-D1 (lithium quinolate,LiQ) or ET-D2.

The electron transport region may include an electron injection layerthat facilitates injection of electrons from the second electrode 190.The electron injection layer may directly contact the second electrode190.

The electron injection layer may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron injection layer may include an alkali metal, an alkalineearth metal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, ora combinations thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In anexample embodiment, the alkali metal may be Li, Na, or Cs. In an exampleembodiment, the alkali metal may be Li or Cs.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare earth metal may be selected from Sc, Y, Ce, Tb, Yb, and Gd.

The alkali metal compound, the alkaline earth-metal compound, and therare earth metal compound may be selected from oxides and halides (forexample, fluorides, chlorides, bromides, or iodides) of the alkalimetal, the alkaline earth-metal, and the rare earth metal.

The alkali metal compound may be selected from alkali metal oxides, suchas Li2O,

Cs₂O, or K₂O, and alkali metal halides, such as LiF, NaF, CsF, KF, LiI,NaI, CsI, or KI. In an example embodiment, the alkali metal compound maybe selected from LiF, Li₂O, NaF, LiI, NaI, CsI, and KI.

The alkaline earth-metal compound may be selected from alkalineearth-metal oxides, such as BaO, SrO, CaO, Ba_(x)Sr_(1-x)O(0<x<1), orBa_(x)Ca_(1-x)O(0<x<1). In an example embodiment, the alkalineearth-metal compound may be selected from BaO, SrO, and CaO.

The rare earth metal compound may be selected from YbF₃, ScF₃, ScO₃,Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In an example embodiment, the rare earthmetal compound may be selected from YbF₃, ScF₃, TbF₃, YbI₃, ScI₃, andTbI₃.

The alkali metal complex, the alkaline earth-metal complex, and the rareearth metal complex may include an ion of alkali metal, alkalineearth-metal, and rare earth metal as described above, and a ligandcoordinated with a metal ion of the alkali metal complex, the alkalineearth-metal complex, or the rare earth metal complex may be selectedfrom hydroxy quinoline, hydroxy isoquinoline, hydroxy benzoquinoline,hydroxy acridine, hydroxy phenanthridine, hydroxy phenyloxazole, hydroxyphenylthiazole, hydroxy diphenyloxadiazole, hydroxy diphenylthiadiazol,hydroxy phenylpyridine, hydroxy phenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, and cyclopentadiene.

The electron injection layer may include or consist of an alkali metal,an alkaline earth metal, a rare earth metal, an alkali metal compound,an alkaline earth-metal compound, a rare earth metal compound, an alkalimetal complex, an alkaline earth-metal complex, a rare earth metalcomplex, or a combinations thereof, as described above. In an exampleembodiment, the electron injection layer may further include an organicmaterial. When the electron injection layer further includes an organicmaterial, an alkali metal, an alkaline earth metal, a rare earth metal,an alkali metal compound, an alkaline earth-metal compound, a rare earthmetal compound, an alkali metal complex, an alkaline earth-metalcomplex, a rare earth metal complex, or a combinations thereof may behomogeneously or non-homogeneously dispersed in a matrix including theorganic material.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within the range describedabove, the electron injection layer may have satisfactory electroninjection characteristics without a substantial increase in drivingvoltage.

[Second Electrode 190]

The second electrode 190 may be disposed on the organic layer 150 havingsuch a structure. The second electrode 190 may be a cathode which is anelectron injection electrode, and in this regard, a material for formingthe second electrode 190 may be selected from metal, an alloy, anelectrically conductive compound, and a combination thereof, which havea relatively low work function.

The second electrode 190 may include at least one selected from lithium(Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium(Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver(Mg—Ag), ITO, and IZO. The second electrode 190 may be a transmissiveelectrode, a semi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have a single-layered structure, or amulti-layered structure including two or more layers.

Layers constituting the hole transport region, an emission layer, andlayers constituting the electron transport region may be formed in acertain region by using one or more suitable methods selected fromvacuum deposition, spin coating, casting, Langmuir-Blodgett (LB)deposition, ink-jet printing, laser-printing, and laser-induced thermalimaging.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed byvacuum deposition, the deposition may be performed at a depositiontemperature of about 100° C. to about 500° C., a vacuum degree of about10⁻⁸ torr to about 10⁻³ torr, and a deposition speed of about 0.01 Å/secto about 100 Å/sec by taking into account a material to be included in alayer to be formed, and the structure of a layer to be formed.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed by spincoating, the spin coating may be performed at a coating speed of about2,000 rpm to about 5,000 rpm and at a heat treatment temperature ofabout 80° C. to about 200° C. by taking into account a material to beincluded in a layer to be formed, and the structure of a layer to beformed.

[General Definition of Substituents]

The term “C₁-C₆₀ alkyl group” as used herein refers to a linear orbranched aliphatic saturated hydrocarbon monovalent group having 1 to 60carbon atoms, and examples thereof include a methyl group, an ethylgroup, a propyl group, an isobutyl group, a sec-butyl group, atert-butyl group, a pentyl group, an isoamyl group, and a hexyl group.The term “C ₁-C₆₀ alkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₆₀ alkyl group.

The term “C₂-C₆₀ alkenyl group” as used herein refers to a hydrocarbongroup having at least one double bond in the middle or at the terminusof the C₂-C₆₀ alkyl group, and examples thereof include an ethenylgroup, a propenyl group, and a butenyl group. The term “C₂-C₆₀alkenylene group” as used herein refers to a divalent group having thesame structure as the C₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a hydrocarbongroup having at least one triple bond in the middle or at the terminusof the C₂-C₆₀ alkyl group, and examples thereof include an ethynylgroup, and a propynyl group. The term “C₂-C₆₀ alkynylene group” as usedherein refers to a divalent group having the same structure as theC₂-C₆₀ alkynyl group.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group),and examples thereof include a methoxy group, an ethoxy group, and anisopropyloxy group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalentsaturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, andexamples thereof include a cyclopropyl group, a cyclobutyl group, acyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term“C₃-C₁₀ cycloalkylene group” as used herein refers to a divalent grouphaving the same structure as the C₃-C₁₀ cycloalkyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein refers to amonovalent monocyclic group having at least one heteroatom selected fromN, O, Si, P, and S as a ring-forming atom and 1 to 10 carbon atoms, andexamples thereof include a 1,2,3,4-oxatriazolidinyl group, atetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term“C₁-C₁₀ heterocycloalkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₁₀ heterocycloalkyl group.

The term C₃-C₁₀ cycloalkenyl group used herein refers to a monovalentmonocyclic group that has 3 to 10 carbon atoms and at least one doublebond in the ring thereof and no aromaticity, and examples thereofinclude a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenylgroup. The term “C₃-C₁₀ cycloalkenylene group” as used herein refers toa divalent group having the same structure as the C₃-C₁₀ cycloalkenylgroup.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein refers to amonovalent monocyclic group that has at least one heteroatom selectedfrom N, O, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms,and at least one double bond in its ring. Non-limiting examples of theC₁-C₁₀ heterocycloalkenyl group include a4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, anda 2,3-dihydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkenylenegroup” as used herein refers to a divalent group having the samestructure as the C₁-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent grouphaving a carbocyclic aromatic system having 6 to 60 carbon atoms, and aC₆-C₆₀ arylene group used herein refers to a divalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms. Non-limitingexamples of the C₆-C₆₀ aryl group include a phenyl group, a naphthylgroup, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, anda chrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylenegroup each include two or more rings, the rings may be fused to eachother.

The term “C₁-C₆₀ heteroaryl group” as used herein refers to a monovalentgroup having a carbocyclic aromatic system that has at least oneheteroatom selected from N, O, Si, P, and S as a ring-forming atom, inaddition to 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylene group”as used herein refers to a divalent group having a carbocyclic aromaticsystem that has at least one heteroatom selected from N, O, Si, P, and Sas a ring-forming atom, in addition to 1 to 60 carbon atoms.Non-limiting examples of the C₁-C₆₀ heteroaryl group include a pyridinylgroup, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group. Whenthe C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group eachinclude two or more rings, the rings may be condensed with each other.

The term “C₆-C₆₀ aryloxy group” as used herein refers to —OA₁₀₂ (whereinA₁₀₂ is the C₆-C₆₀ aryl group), and a C₆-C₆₀ arylthio group used hereinindicates —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

The term “monovalent non-aromatic condensed polycyclic group” as usedherein refers to a monovalent group (for example, having 8 to 60 carbonatoms) having two or more rings condensed with each other, only carbonatoms as ring-forming atoms, and at least one non-aromatic ring in itsentire molecular structure. A detailed example of the monovalentnon-aromatic condensed polycyclic group is a fluorenyl group. The term“divalent non-aromatic condensed polycyclic group” as used herein refersto a divalent group having the same structure as the monovalentnon-aromatic condensed polycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” asused herein refers to a monovalent group (for example, having 1 to 60carbon atoms) having two or more rings condensed to each other, at leastone heteroatom selected from N, O, Si, P, and S, other than carbonatoms, as a ring-forming atom, and at least one non-aromatic ring in itsentire molecular structure. An example of the monovalent non-aromaticcondensed heteropolycyclic group is a carbazolyl group. The term“divalent non-aromatic condensed heteropolycyclic group” as used hereinrefers to a divalent group having the same structure as the monovalentnon-aromatic condensed heteropolycyclic group.

The term “C₅-C₆₀ carbocyclic group” as used herein refers to amonocyclic or polycyclic group having 5 to 60 carbon atoms in which aring-forming atom is a carbon atom only. The C₅-C₆₀ carbocyclic groupmay be an aromatic carbocyclic group or a non-aromatic carbocyclicgroup. The C₅-C₆₀ carbocyclic group may be a ring, such as benzene, amonovalent group, such as a phenyl group, or a divalent group, such as aphenylene group. In an example embodiment, depending on the number ofsubstituents connected to the C₅-C₆₀ carbocyclic group, the C₅-C₆₀carbocyclic group may be a trivalent group or a quadrivalent group.

The term “C₁-C₆₀ heterocyclic group” as used herein refers to a grouphaving the same structure as the C₅-C₆₀ carbocyclic group, except thatas a ring-forming atom, at least one heteroatom selected from N, O, Si,P, and S is used in addition to carbon (the number of carbon atoms maybe in a range of 1 to 60).

In the specification, at least one substituent of the substituted C₅-C₆₀carbocyclic group, the substituted C₁-C₆₀ heterocyclic group, thesubstituted C₃-C₁₀ cycloalkylene group, the substituted C₁-C₁₀heterocycloalkylene group, the substituted C₃-C₁₀ cycloalkenylene group,the substituted C₁-C₁₀ heterocycloalkenylene group, the substitutedC₆-C₆₀ arylene group, the substituted C₁-C₆₀ heteroarylene group, thesubstituted divalent non-aromatic condensed polycyclic group, thesubstituted divalent non-aromatic condensed heteropolycyclic group, thesubstituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group,the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxygroup, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group may be selectedfrom:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group. each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁),and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently beselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁ ₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a C₁-C₆₀ alkylgroup substituted with at least one selected from deuterium, —F, and acyano group, a C₆-C₆₀ aryl group substituted with at least one selectedfrom deuterium, —F, and a cyano group, a biphenyl group, and a terphenylgroup.

The term “Ph” as used herein represents a phenyl group, the term “Me” asused herein represents a methyl group, the term “Et” as used hereinrepresents an ethyl group, the term “ter-Bu” or “Bu^(t,)” as usedherein, represents a tert-butyl group, and the term “OMe” as used hereinrepresents a methoxy group.

The term “biphenyl group” as used herein refers to a “phenyl groupsubstituted with a phenyl group. The “biphenyl group” is a “substitutedphenyl group” having a “C₆-C₆₀ aryl group” as a substituent.

The term “terphenyl group” as used herein refers to a “phenyl groupsubstituted with a biphenyl group. The “terphenyl group” is a “phenylgroup” having, as a substituent, a “C₆-C₆₀ aryl group substituted with aC₆-C₆₀ aryl group.”

* and *′ as used herein, unless defined otherwise, each refer to abinding site to a neighboring atom in a corresponding formula.

The following Examples and Comparative Examples are provided in order tohighlight characteristics of one or more embodiments, but it will beunderstood that the Examples and Comparative Examples are not to beconstrued as limiting the scope of the embodiments, nor are theComparative Examples to be construed as being outside the scope of theembodiments. Further, it will be understood that the embodiments are notlimited to the particular details described in the Examples andComparative Examples.

The expression “B was used instead of A” used in describing SynthesisExamples means that an identical number of molar equivalents of A wasused in place of molar equivalents of B.

SYNTHESIS EXAMPLES Synthesis Example 1 Synthesis of Compound 4

1) Synthesis of Intermediate [4-A]

9.35 g (50 mmol) of bromoanisole, 3.40 g (50 mmol) of imidazole, 23 g(100 mmol) of potassium triphosphate, 1.83 g (10 mmol) of iodine copper,and 1.17 g (10 mmol) of picolinic acid were added to a reactioncontainer and suspended in 100 mL of dimethyl sulfoxide. The reactionmixture was heated and stirred at a temperature of 160° C. for 24 hours.After the reaction was completed, the reaction product was cooled toroom temperature, 300 mL of distilled water was added thereto, and anorganic layer was extracted therefrom by using ethyl acetate. Theextracted organic layer was washed with a saturated aqueous sodiumchloride solution and dried by using sodium sulfate. A residue, fromwhich a solvent was removed, was separated by column chromatography toobtain 6.97 g (40 mmol) of Intermediate [4-A].

2) Synthesis of Intermediate [4-B]

6.97 g (40 mmol) of Intermediate [4-A] was suspended in an excess ofbromic acid solution. The reaction mixture was heated and stirred at atemperature of 110° C. for 24 hours. After the reaction was completed,the reaction product was cooled to room temperature and neutralized byadding an appropriate amount of sodium hydrogen carbonate thereto. 300mL of distilled water was added thereto and an organic layer wasextracted therefrom by using ethyl acetate. The extracted organic layerwas washed with a saturated aqueous sodium chloride solution and driedby using sodium sulfate. A residue, from which a solvent was removed,was separated by column chromatography to obtain 5.77 g (36 mmol) ofIntermediate [4-B].

3) Synthesis of Intermediate [4-C]

11.80 g (50 mmol) of 1,3-dibromobenzene, 3.40 g (50 mmol) of imidazole,23 g (100 mmol) of potassium triphosphate, 1.83 g (10 mmol) of iodinecopper, and 1.17 g (10 mmol) of picolinic acid were added to a reactioncontainer and suspended in 100 mL of dimethyl sulfoxide. The reactionmixture was heated and stirred at a temperature of 160° C. for 24 hours.After the reaction was completed, the reaction product was cooled toroom temperature, 300 mL of distilled water was added thereto, and anorganic layer was extracted therefrom by using ethyl acetate. Theextracted organic layer was washed with a saturated aqueous sodiumchloride solution and dried by using sodium sulfate. A residue, fromwhich a solvent was removed, was separated by column chromatography toobtain 7.81 g (35 mmol) of Intermediate [4-C].

4) Synthesis of Intermediate [4-D]

5.77 g (36 mmol) of Intermediate [4-B], 7.81 g (35 mmol) of Intermediate[4-C], 16.1 g (70 mmol) of potassium triphosphate, 1.28 g (7 mmol) ofiodine copper, and 0.82 g (7 mmol) of picolinic acid were added to areaction container and suspended in 70 mL of dimethyl sulfoxide. Thereaction mixture was heated and stirred at a temperature of 160° C. for24 hours. After the reaction was completed, the reaction product wascooled to room temperature, 300 mL of distilled water was added thereto,and an organic layer was extracted therefrom by using ethyl acetate. Theextracted organic layer was washed with a saturated aqueous sodiumchloride solution and dried by using sodium sulfate. A residue, fromwhich a solvent was removed, was separated by column chromatography toobtain 8.47 g (28 mmol) of Intermediate [4-D].

5) Synthesis of Intermediate [4-E]

8.47 g (28 mmol) of Intermediate [4-D] and 1.68 g (140 mmol) of1,2-diiodocyclohexane were added to a reaction container and suspendedin 100 mL of toluene. The reaction mixture was heated and stirred at atemperature of 110° C. for 24 hours. After the reaction was completed,the reaction product was cooled to room temperature, and a solidgenerated therefrom was filtered and washed with ether. The washed solidwas dried to obtain 12.5 g (19.6 mmol) of Intermediate [4-E].

6) Synthesis of Intermediate [4-F]

12.5 g (19.6 mmol) of Intermediate [4-E] and 9.58 g (58.8 mmol) ofammonium hexafluorophosphate were suspended in 50 mL of methyl alcoholand 50 mL of water. The reaction mixture was stirred at room temperaturefor 24 hours. After the reaction was completed, a solid generatedtherefrom was filtered and washed with ether. The washed solid was driedto obtain 9.25 g (13.7 mmol) of Intermediate [4-F].

7) Synthesis of Compound 4

9.25 g (13.7 mmol) of Intermediate [4-F], 5.6 g (15 mmol) ofdichloro(1,5-cyclooctadiene)platinum, and 3.4 g (41 mmol) of sodiumacetate were suspended in 160 mL of dioxane. The reaction mixture washeated and stirred at a temperature of 110° C. for 72 hours. After thereaction was completed, the reaction product was cooled to roomtemperature, 300 mL of distilled water was added thereto, and an organiclayer was extracted therefrom by using ethyl acetate. The extractedorganic layer was washed with a saturated aqueous sodium chloridesolution and dried by using sodium sulfate. A residue, from which asolvent was removed, was separated by column chromatography to obtain2.37 g (4.1 mmol) of Compound 4.

Synthesis Example 2: Synthesis of Compound 9

1) Synthesis of Intermediate [9-A]

8.75 g (50 mmol) of 1-bromo-3-fluorobenzene was suspended in 100 mL oftetrahydrofuran and stirred at a temperature of -78° C. 24 mL of n-BuLisolution (2.5 M in hexane) was added to the mixed solution and stirredat the same temperature for 2 hours. After the stirring, 7.74 g (60mmol) of dimethyldichlorosilane was added thereto and further stirred atroom temperature for 24 hours. After the reaction was completed, 300 mLof distilled water was added thereto, and an organic layer was extractedtherefrom by using ethyl acetate. The extracted organic layer was washedwith a saturated aqueous sodium chloride solution and dried by usingsodium sulfate. A residue, from which a solvent was removed, wasseparated by column chromatography to obtain 9.93 g (40 mmol) ofIntermediate [9-A].

2) Synthesis of Intermediate [9-B]

9.93 g (40 mmol) of Intermediate [9-A], 8.17 g (120 mmol) of imidazole,and 36.8 g (160 mmol) of potassium triphosphate were added to a reactioncontainer and suspended in 80 mL of dimethyl sulfoxide. The reactionmixture was heated and stirred at a temperature of 160° C. for 24 hours.After the reaction was completed, the reaction product was cooled toroom temperature, 300 mL of distilled water was added thereto, and anorganic layer was extracted therefrom by using ethyl acetate. Theextracted organic layer was washed with a saturated aqueous sodiumchloride solution and dried by using sodium sulfate. A residue, fromwhich a solvent was removed, was separated by column chromatography toobtain 9.0 g (26 mmol) of Intermediate [9-B].

3) Synthesis of Intermediate [9-C]

9.0 g (26 mmol) of Intermediate [9-B] and 1.56 g (130 mmol) of1,2-diiodocyclohexane were added to a reaction container and suspendedin 100 mL of toluene. The reaction mixture was heated and stirred at atemperature of 110° C. for 24 hours. After the reaction was completed,the reaction product was cooled to room temperature, and a solidgenerated therefrom was filtered and washed with ether. The washed solidwas dried to obtain 12.4 g (18.2 mmol) of Intermediate [9-C].

4) Synthesis of Intermediate [9-D]

12.4 g (18.2 mmol) of Intermediate [9-C] and 8.9 g (54.6 mmol) ofammonium hexafluorophosphate were added to a reaction container andsuspended in 50 mL of methyl alcohol and 50 mL of water. The reactionmixture was stirred at room temperature for 24 hours. After the reactionwas completed, a solid generated therefrom was filtered and washed withether. The washed solid was dried to obtain 8.48 g (11.8 mmol) ofIntermediate [9-D].

5) Synthesis of Compound 9

8.48 g (11.8 mmol) of Intermediate [9-D], 4.85 g (13 mmol) ofdichloro(1,5-cyclooctadiene)platinum, and 2.94 g (35.4 mmol) of sodiumacetate were suspended in 140 mL of dioxane. The reaction mixture washeated and stirred at a temperature of 110° C. for 72 hours. After thereaction was completed, the reaction product was cooled to roomtemperature, 300 mL of distilled water was added thereto, and an organiclayer was extracted therefrom by using ethyl acetate. The extractedorganic layer was washed with a saturated aqueous sodium chloridesolution and dried by using sodium sulfate. A residue, from which asolvent was removed, was separated by column chromatography to obtain1.11 g (1.8 mmol) of Compound 9.

Synthesis Example 3: Synthesis of Compound 14

1) Synthesis of Intermediate [14-A]

8.75 g (50 mmol) of 1-bromo-3-fluorobenzene was suspended in 100 mL oftetrahydrofuran and stirred at a temperature of −78° C. 24 mL of n-BuLisolution (2.5 M in hexane) was added to the mixed solution and stirredat the same temperature for 2 hours. After the stirring, 9.51 g (60mmol) of 3-fluorobenzoyl chloride was added thereto and further stirredat room temperature for 24 hours. After the reaction was completed, 300mL of distilled water was added thereto, and an organic layer wasextracted therefrom by using ethyl acetate. The extracted organic layerwas washed with a saturated aqueous sodium chloride solution and driedby using sodium sulfate. A residue, from which a solvent was removed,was separated by column chromatography to obtain 8.29 g (38 mmol) ofIntermediate [14-A].

2) Synthesis of Intermediate [14-B]

10.7 g (45.6 mmol) of 2-bromobiphenyl, 11.1 g (45.6 mmol) of magnesium,and a catalytic amount of iodine were suspended in 100 mL oftetrahydrofuran and refluxed for 3 hours to generate a Grignard reagent.8.29 g (38 mmol) of Intermediate [14-A] was further added to the mixtureand refluxed for 24 hours. After the reaction was completed, thereaction product was cooled to room temperature, and 300 mL of distilledwater was added thereto, and an organic layer was extracted therefrom byusing ethyl acetate. The extracted organic layer was washed with asaturated aqueous sodium chloride solution and dried by using sodiumsulfate. A residue, from which a solvent was removed, was separated bycolumn chromatography to obtain 10.6 g (28.5 mmol) of Intermediate[14-B].

3) Synthesis of Intermediate [14-C]

10.6 g (28.5 mmol) of Intermediate [14-B] was added to an excess ofhydrochloric acid/acetic acid solution and refluxed for 24 hours. Afterthe reaction was completed, the reaction product was cooled to roomtemperature, and 300 mL of distilled water was added thereto, and anorganic layer was extracted therefrom by using ethyl acetate. Theextracted organic layer was washed with a saturated aqueous sodiumchloride solution and dried by using sodium sulfate. A residue, fromwhich a solvent was removed, was separated by column chromatography toobtain 8.59 g (24.2 mmol) of Intermediate [14-C].

4) Synthesis of Intermediate [14-D]

8.59 g (24.2 mmol) of Intermediate [14-C] and 1.45 g (121 mmol) ofimidazole were added to a reaction container and suspended in 100 mL oftoluene. The reaction mixture was heated and stirred at a temperature of110° C. for 24 hours. After the reaction was completed, the reactionproduct was cooled to room temperature, and a solid generated therefromwas filtered and washed with ether. The washed solid was dried to obtain7.61 g (9.68 mmol) of Intermediate [14-D].

5) Synthesis of Intermediate [14-E]

7.61 g (9.68 mmol) of Intermediate [14-D] and 4.72 g (29 mmol) ofammonium hexafluorophosphate were added to a reaction container andsuspended in 20 mL of methyl alcohol and 20 mL of water. The reactionmixture was stirred at room temperature for 24 hours. After the reactionwas completed, a solid generated therefrom was filtered and washed withether. The washed solid was dried to obtain 6.37 g (7.74 mmol) ofIntermediate [14-E].

6) Synthesis of Compound 14

6.37 g (7.74 mmol) of Intermediate [14-E], 3.2 g (8.51 mmol) ofdichloro(1,5-cyclooctadiene)platinum, and 1.92 g (23.2 mmol) of sodiumacetate were suspended in 90 mL of dioxane. The reaction mixture washeated and stirred at a temperature of 110° C. for 72 hours. After thereaction was completed, the reaction product was cooled to roomtemperature, 300 mL of distilled water was added thereto, and an organiclayer was extracted therefrom by using ethyl acetate. The extractedorganic layer was washed with a saturated aqueous sodium chloridesolution and dried by using sodium sulfate. A residue, from which asolvent was removed, was separated by column chromatography to obtain1.34 g (1.86 mmol) of Compound 14.

Synthesis Example 4

Synthesis of Compound 19

Compound 19 was obtained in the same manner as in Synthesis Example 2,except that dichloro(2,4,6-trimethylphenyl)borane was used instead ofdimethyldichlorosilane.

Synthesis Example 5 Synthesis of Compound 24

Compound 24 was obtained in the same manner as in Synthesis Example 1,except that 4,5-dimethyl-1H-imidazole was used instead of imidazole.

¹H NMR and MS/FAB of the compounds synthesized in Synthesis Examples 1to 5 are shown in Table 1.

Synthesis methods of compounds other than Compounds shown in Table 1 mayalso be easily recognized by those of skill in the art by referring tothe synthesis mechanisms and methods described above.

TABLE 1 MS/FAB Compound ¹H NMR (CDCl₃, 400 MHz) found calc. 4 0.82-1.81(8H, m), 2.62 (2H, m), 6.45-6.55 (6H, m), 575.1290 575.1285 7.10 (2H,m), 8.55 (2H, m) 9 0.25 (6H, s), 1.11-1.89 (8H, m), 2.52 (2H, m), 5.83617.1584 617.1574 (1H, m), 6.31 (2H, m), 6.52 (2H, m), 6.81 (2H, m),7.22 (1H, m), 8.74 (2H, m) 14 1.1-1.98 (8H, m), 2.65 (2H, m), 6.57 (2H,m), 6.71- 723.1953 723.1962 6.82 (4H, m), 7.09-7.48 (8H, m), 7.91 (2H,m), 8.75 (2H, m) 19 0.81-1.91 (8H, m), 2.18 (3H, s), 2.41 (6H, s), 2.42689.2285 689.2290 (2H, m), 6.46 (2H, m), 6.81 (2H, m), 7.01 (2H, m),7.24-7.65 (4H, m), 8.51 (2H, m) 24 0.84-1.85 (8H, m), 2.31 (12H, s) 2.63(2H, m), 6.41- 631.1910 631.1911 6.45 (4H, m), 7.12 (2H, m)

EXAMPLES Example 1

As a substrate and an ITO anode, a Corning 15 Ω/cm² (1,200 Å) ITO glasssubstrate was cut to a size of 50 mm×50 mm×0.7 mm, sonicated withisopropyl alcohol and pure water each for 5 minutes, and then cleaned byexposure to ultraviolet rays and ozone for 30 minutes. Then, the ITOglass substrate was provided to a vacuum deposition apparatus.

With reference to the compounds illustrated below, 2-TNATA wasvacuum-deposited on the ITO anode formed on the ITO glass substrate toform a hole injection layer having a thickness of 600 Å, and NPB wasvacuum-deposited on the hole injection layer to form a hole transportlayer having a thickness of 300 Å.

BCPDS and POPCPA (BCPDS to POPCPA weight ratio of 1:1) as a co-host andCompound 4 as a dopant were co-deposited on the hole transport layer asa co-host to dopant weight ratio of 90:10 to form an emission layerhaving a thickness of 300 Å.

TSPO1 was deposited on the emission layer to form a hole blocking layerhaving a thickness of 50 Å, Alga was deposited on the hole blockinglayer to form an electron transport layer having a thickness of 300 Å,LiF was deposited on the electron transport layer to form an electroninjection layer having a thickness of 10 Å, and Al was vacuum-depositedon the electron injection layer to form a cathode having a thickness of3,000 Å, thereby completing the manufacture of an organic light-emittingdevice.

Examples 2 to 5 and Comparative Examples 1 to 4

Organic light-emitting devices were manufactured in the same manner asin Example 1, except that the compounds shown in Table 2 were each usedinstead of Compound 1 as a dopant in forming an emission layer.

Evaluation Example 1

The driving voltage, current density, brightness, luminance efficiency,emission color, and wavelength of maximum emission of the organiclight-emitting devices manufactured according to Examples 1 to 5 andComparative Examples 1 to 4 were measured by using Keithley SMU 236 anda luminance meter PR650, and results thereof are shown in Table 2.

TABLE 2 wavelength of Driving Current Luminance maximum Dopant voltagedensity Brightness efficiency Emission emission compound (V) (mA/cm²)(cd/m²) (cd/A) color (nm) Example 1 Compound 4 5.30 50 4125 8.25 Blue490 Example 2 Compound 9 5.45 50 4025 8.05 Blue 470 Example 3 Compound14 5.55 50 4033 8.07 Blue 474 Example 4 Compound 19 5.43 50 4024 8.05Blue 468 Example 5 Compound 24 5.58 50 4055 8.11 Blue 495 ComparativeFIrpic 6.56 50 3870 7.74 Blue 478 Example 1 Comparative Compound A 7.1050 2957 6.89 Blue 460 Example 2 Comparative Compound B 6.83 50 3800 7.34Blue 500 Example 3 Comparative Compound C 6.23 50 3759 7.12 Blue 480Example 4

Referring to Table 2, it can be seen that the organic light-emittingdevices of Examples 1 to 5 had a low driving voltage and high brightnessand luminance efficiency, as compared with those of the organiclight-emitting devices of Comparative Examples 1 to 4.

As described above, an organic light-emitting device including theorganometallic compound may have a low driving voltage, high brightness,and high luminance efficiency.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the claims.

What is claimed is:
 1. An organic light-emitting device, comprising: afirst electrode; a second electrode; and an organic layer between thefirst electrode and the second electrode and including an emissionlayer, the organic layer including an organometallic compoundrepresented by Formula 1:

wherein, in Formula 1, M₁₁ is platinum (Pt), palladium (Pd), copper(Cu), silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium(Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium(Eu), terbium (Tb), or thulium (Tm), Y₁₀, Y₂₀, Y₃₀, and Y₄₀ are eachindependently N or C, Y₁₁, Y₁₂, Y₂₁, Y₂₂, Y₃₁, Y₃₂, Y₄₁, and Y₄₂ areeach independently N or C, A₁₀, A₂₀, A₃₀, and A₄₀ are each independentlya C₅-C₆₀ carbocyclic group or a C₁-C₆₀ heterocyclic group, T₁₁ to T₁₄are each independently a single bond, *—O—*′, or *—S—*′, L₁₁ is asubstituted or unsubstituted C₃-C₁₀ cycloalkylene group, *—O—*′, *—S—*′,*—C(R₁)(R₂)—*′, *—C(R₁)═*′, *═C(R₁)—*′, *—C(R₁)═C(R₂)—*′, *—C(═O)—*′,*—C(═S)—*′, *—C≡C—*′, *—B(R₁)—*′, *—N(R₁)—*′, *—P(R₁)—*′,*—Si(R₁)(R₂)—*′, *—P(R₁)(R₂)—*′, or *—Ge(R₁)(R₂)—*′, a11 is 1, 2, 3, 4,or 5, at least one of L₁₁(s) in the number of a11 is a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, L₁₂ to L₁₄ are eachindependently a single bond, *—O—*′, *—S—*′, *—C(R₁)(R₂)—*′, *—C(R₁)═*′,*═C(R₁)—*′, *—C(R₁)═C(R₂)—*′, *—C(═O)—*′, *—C(═S)—*′, *—C≡C—*′,*—B(R₁)—*′, *—N(R₁)—*′, *—P(R₁)—*′, *—Si(R₁)(R₂)—*′, *—P(R₁)(R₂)—*′, or*—Ge(R₁)(R₂)—*′, a12, a13, and a14 are each independently 0, 1, 2, 3, 4,or 5, R₁, R₂, R₁₀, R₂₀, R₃₀, and R₄₀ are each independently hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedC₁-C₆₀ heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), or —P(═S)(Q₁)(Q₂), R₁ and R₂are optionally linked to form a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀ heterocyclicgroup, R₁ and R₁₀; R₁ and R₂₀; R₁ and R₃₀; or R₁ and R₄₀ are optionallylinked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic groupor a substituted or unsubstituted C₁-C₆₀ heterocyclic group, b10, b20,b30, and b40 are each independently 1, 2, 3, 4, 5, 6, 7, or 8, * and *′each indicate a binding site to a neighboring atom, at least onesubstituent of the substituted C₅-C₆₀ carbocyclic group, the substitutedC₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenylgroup, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substitutedC₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenylgroup, the substituted C₁-C₁₀ heterocycloalkenyl group, the substitutedC₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substitutedC₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, thesubstituted monovalent non-aromatic condensed polycyclic group, and thesubstituted monovalent non-aromatic condensed heteropolycyclic group is:deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, or a C₁-C₆₀ alkoxy group, each substituted withdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃),—N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), or—P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, or a monovalent non-aromatic condensed heteropolycyclic group; aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,or a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂),—B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), or —P(═O)(Q₂₁)(Q₂₂); or—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), or —P(═O)(Q₃₁)(Q₃₂), and Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃,and Q₃₁ to Q₃₃ are each independently hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, aC₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a C₁-C₆₀ alkyl group substituted withdeuterium, —F, or a cyano group, a C₆-C₆₀ aryl group substituted withdeuterium, —F, or a cyano group, a biphenyl group, or a terphenyl group.2. The organic light-emitting device as claimed in claim 1, wherein: thefirst electrode is an anode, the second electrode is a cathode, theorganic layer further includes a hole transport region between the firstelectrode and the emission layer and an electron transport regionbetween the emission layer and the second electrode, the hole transportregion includes at least one of a hole injection layer, a hole transportlayer, a buffer layer, an emission auxiliary layer, and an electronblocking layer, and the electron transport region includes at least oneof a hole blocking layer, an electron transport layer, and an electroninjection layer.
 3. The organic light-emitting device as claimed inclaim 2, wherein the emission layer includes the organometalliccompound.
 4. The organic light-emitting device as claimed in claim 1,wherein the emission layer emits blue light having a wavelength ofmaximum emission of about 440 nm to about 500 nm.
 5. The organiclight-emitting device as claimed in claim 3, wherein: the emission layerincludes a host and a dopant, and the dopant includes the organometalliccompound.
 6. The organic light-emitting device as claimed in claim 3,wherein: the emission layer further includes a host, and the hostincludes a silyl-containing compound, a phosphine oxide-containingcompound, or a combination thereof.
 7. The organic light-emitting deviceas claimed in claim 2, wherein: the electron transport region includes ahole blocking layer, the hole blocking layer directly contacts theemission layer, and the hole blocking layer includes a phosphineoxide-containing compound or a silyl-containing compound.
 8. Anorganometallic compound represented by Formula 1:

wherein M₁₁ is platinum (Pt), palladium (Pd), copper (Cu), silver (Ag),gold (Au), rhodium (Rh), iridium (Ir), ruthenium (Ru), osmium (Os),titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium(Tb), or thulium (Tm), Y₁₀, Y₂₀, Y₃₀, and Y₄₀ are each independently Nor C, Y₁₁, Y₁₂, Y₂₁, Y₂₂, Y₃₁, Y₃₂, Y₄₁, and Y₄₂ are each independentlyN or C, A₁₀, A₂₀, A₃₀, and A₄₀ are each independently a C₅-C₆₀carbocyclic group or a C₁-C₆₀ heterocyclic group, T₁₁ to T₁₄ are eachindependently a single bond, *—O—*′, or *—S—*′, L₁₁ is a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, *—O—*′, *—S—*′,*—C(R₁)(R₂)—*′, *—C(R₁)═*′, *═C(R₁)*′, *—C(R₁)═C(R₂)—*′, *—C(═O)—*′,*—C(═S)—*′, *—C≡C—*′, *—B(R₁)—*′, *—N(R₁)—*′, *—P(R₁)—*′,*—Si(R₁)(R₂)—*′, *—P(R₁)(R₂)—*′, or *—Ge(R₁)(R₂)—*′, a11 is 1, 2, 3, 4,or 5, at least one of L₁₁(s) in the number of a11 is a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, L₁₂ to L₁₄ are eachindependently a single bond, *—O—*′, *—S—*′, *—C(R₁)(R₂)—*′, *—N(R₁)—*′,*—P(R₁)—*′, *—Si(R₁)(R₂)—*′, *—P(R₁)(R₂)—*′, or *—Ge(R₁)(R₂)—*′, a12,a13, and a14 are each independently 0, 1, 2, 3, 4, or 5, R₁, R₂, R₁₀,R₂₀, R₃₀, and R₄₀ are each independently hydrogen, deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedC₁-C₆₀ heteroaryloxy group, a substituted or unsubstituted C₁-C₆₀heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), or —P(═S)(Q₁)(Q₂), R₁ and R₂are optionally linked to form a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀ heterocyclicgroup, R₁ and R₁₀; R₁ and R₂₀; R₁ and R₃₀; or R₁ and R₄₀ are optionallylinked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic groupor a substituted or unsubstituted C₁-C₆₀ heterocyclic group, b10, b20,b30, and b40 are each independently 1, 2, 3, 4, 5, 6, 7, or 8, * and *′each indicate a binding site to a neighboring atom, at least onesubstituent of the substituted C₅-C₆₀ carbocyclic group, the substitutedC₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenylgroup, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substitutedC₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenylgroup, the substituted C₁-C₁₀ heterocycloalkenyl group, the substitutedC₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substitutedC₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, thesubstituted monovalent non-aromatic condensed polycyclic group, and thesubstituted monovalent non-aromatic condensed heteropolycyclic group is:deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, or a C₁-C₆₀ alkoxy group, each substituted withdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃),—N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), or—P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, or a monovalent non-aromatic condensed heteropolycyclic group; aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,or a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂),—B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), or —P(═O)(Q₂₁)(Q₂₂); or—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), or —P(═O)(Q₃₁)(Q₃₂), and Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃,and Q₃₁ to Q₃₃ are each independently hydrogen, deuterium, —F, -CI, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, aC₁-C₆₀ heteroaryloxy group, a C₁-C₆₀ heteroarylthio group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a C₁-C₆₀ alkyl group substituted withdeuterium, —F, or a cyano group, a C₆-C₆₀ aryl group substituted withdeuterium, —F, or a cyano group, a biphenyl group, or a terphenyl group.9. The organometallic compound as claimed in claim 8, wherein M₁₁ is Pt,Pd, Cu, Ag, or Au.
 10. The organometallic compound as claimed in claim8, wherein: at least one of Y₁₀ and Y₂₀ is C, (i) when Y₁₀ is C, a bondbetween Y₁₀ and T₁₁ or a bond between Y₁₀ and M₁₁ is a coordinate bond,and (ii) when Y₂₀ is C, a bond between Y₂₀ and T₁₂ or a bond between Y₂₀and M₁₁ is a coordinate bond.
 11. The organometallic compound as claimedin claim 8, wherein at least one of A₁₀ and A₂₀ is an N-containingC₁-C₆₀ heterocyclic group.
 12. The organometallic compound as claimed inclaim 8, wherein A₁₀ and A₂₀ are each independently a group representedby one of Formulae 10-1 to 10-3:

wherein, in Formulae 10-1 to 10-3, Y₁₃ to Y₁₈ and X₁₁ to X₁₄ are eachindependently N or C(R₁₀), R₁₀ is the same as described in connectionwith R₁₀ in claim 8, and *, *′, and *41 each indicate a binding site toa neighboring atom.
 13. The organometallic compound as claimed in claim8, wherein A₃₀ and A₄₀ are each independently a group represented by oneof Formula 2-1 to 2-43:

wherein, in Formulae 2-1 to 2-43, X₂₁ to X₂₃ are each independentlyC(R₂₄) or C—*, provided that at least two of X₂₁ to X₂₃ are C—*, X₂₄ isN—*, and X₂₅ and X₂₆ are each independently C(R₂₄) or C—*, provided thatat least one of X₂₅ and X₂₆ is C—*, X₂₇ and X₂₈ are each independentlyN, N(R₂₅), or N—*, and X₂₉ is C(R₂₄) or C—*, provided that i) at leastone of X₂₇ and X₂₈ is N—*, and X₂₉ is C—*, or ii) X₂₇ and X₂₈ are eachN—*, and X₂₉ is C(R₂₄), R₂₁ to R₂₅ are each independently the same asdescribed in connection with R₁₀ in claim 8, b21 is 1, 2, or 3, b22 is1, 2, 3, 4, or 5, b23 is 1, 2, 3, or 4, b24 is 1 or 2, and * indicates abinding site to a neighboring atom.
 14. The organometallic compound asclaimed in claim 8, wherein: each of T₁₁ to T₁₄ is a single bond; T₁₁ isO or S, and T₁₂ to T₁₄ are each a single bond; T₁₂ is O or S, and T₁₁,T₁₃, and T₁₄ are each a single bond; T₁₃ is O or S, and T₁₁, T₁₂, andT₁₄ are each a single bond; or T₁₄ is O or S, and T₁₁, T₁₂, and T₁₃ areeach a single bond.
 15. The organometallic compound as claimed in claim8, wherein at least one of L₁₁(s) in the number of a11 is: acyclopropylene group, a cyclobutylene group, a cyclopentylene group, acyclohexylene group, a cycloheptylene group, a cyclooctylene group, acyclononylene group, or a cyclodecanylene group; or a cyclopropylenegroup, a cyclobutylene group, a cyclopentylene group, a cyclohexylenegroup, a cycloheptylene group, a cyclooctylene group, a cyclononylenegroup, or a cyclodecanylene group, each substituted with deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a phenanthrenyl group, ananthracenyl group, a triperylenyl group, a pyridinyl group, apyrimidinyl group, a carbazolyl group, a triazinyl group, adibenzofuranyl group, or a dibenzothiophenyl group.
 16. Theorganometallic compound as claimed in claim 8, wherein at least one ofL₁₁(s) in the number of a11 is a group represented by one of Formulae3-1 to 3-5:

wherein, in Formulae 3-1 to 3-5, R₃ is hydrogen, deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkenyl group, a C₁-C₂₀ alkynyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a phenanthrenyl group, ananthracenyl group, a triperylenyl group, a pyridinyl group, apyrimidinyl group, a carbazolyl group, a triazinyl group, adibenzofuranyl group, or a dibenzothiophenyl group, b4 is an integerfrom 1 to 4, b6 is an integer from 1 to 6, b8 is an integer from 1 to 8,b10 is an integer from 1 to 10, b12 is an integer from 1 to 12, and *and *′ each indicate a binding site to a neighboring atom.
 17. Theorganometallic compound as claimed in claim 8, wherein: L₁₂ and L₁₄ areeach a single bond, and L₁₃ is *—O—*′, *—S—*′, *—N(R₁)—*′,*—C(R₁)(R₂)—*′, *—Si(R₁)(R₂)—*′, or *—B(R₁)—*′.
 18. The organometalliccompound as claimed in claim 8, wherein R₁, R₂, R₁₀, R₂₀, R₃₀, and R₄₀are each independently: hydrogen, deuterium, —F, —Cl, —Br, —I, a cyanogroup, a C₁-C₂₀ alkyl group, or a C₁-C₂₀ alkoxy group; a C₁-C₂₀ alkylgroup or a C₁-C₂₀ alkoxy group, each substituted with deuterium, —F,—Cl, —Br, —I, a cyano group, a phenyl group, or a biphenyl group; agroup represented by one of Formulae 5-1 to 5-25; or a group representedby one of Formulae 6-1 to 6-55, and R₁ and R₂ are optionally linked toform a cyclopentane group, a cyclohexane group, a benzene group, anaphthylene group, or a fluorene group:

wherein, in Formulae 5-1 to 5-25 and 6-1 to 6-55, Y₃₁ is O, S,C(Z₃₄)(Z₃₅), N(Z₃₄), Or Si(Z₃₄)(Z₃₅), Z₃₁ to Z₃₅ are each independentlyhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, a C₂-C₂₀ alkynyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, aphenanthrenyl group, an anthracenyl group, a triperylenyl group, apyridinyl group, a pyrimidinyl group, a carbazolyl group, or a triazinylgroup, e2 is 1 or 2, e3 is an integer from 1 to 3, e4 is an integer from1 to 4, e5 is an integer from 1 to 5, e6 is an integer from 1 to 6, e7is an integer from 1 to 7, e9 is an integer from 1 to 9, and * indicatesa binding site to a neighboring atom.
 19. The organometallic compound asclaimed in claim 8, wherein R₁, R₂, R₁₀, R₂₀, R₃₀, and R₄₀ are eachindependently: hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, aC₁-C₂₀ alkyl group, or a C₁-C₂₀ alkoxy group; a C₁-C₂₀ alkyl group or aC₁-C₂₀ alkoxy group, each substituted with deuterium, —F, —Cl, —Br, —I,a cyano group, a phenyl group, or a biphenyl group; a phenyl group, abiphenyl group, a terphenyl group, a pentalenyl group, an indenyl group,a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a carbazolyl group, an acridinyl group,a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, or a dibenzocarbazolyl group; or a phenyl group, a biphenylgroup, a terphenyl group, a pentalenyl group, an indenyl group, anaphthyl group, an azulenyl group, an indacenyl group, an acenaphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a carbazolyl group, an acridinyl group,a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, or a dibenzocarbazolyl group, each substituted with deuterium,—F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, or a biphenyl group, and R₁ and R₂ are optionallylinked to form a cyclopentane group, a cyclohexane group, or a fluorenegroup.
 20. The organometallic compound as claimed in claim 8, whereinthe organometallic compound represented by Formula 1 is one of Compounds1 to 40: